Add RetainedRef uses where needed.

chrome/browser/sync_file_system/drive_backend/callback_helper_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/sync_file_system/drive_backend/callback_helper.h"
 
 #include "base/location.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/thread_task_runner_handle.h"
@@ skipping 56 matching lines @@
   thread.Start();
 
   scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner =
       base::ThreadTaskRunnerHandle::Get();
   scoped_refptr<base::SequencedTaskRunner> worker_task_runner =
       thread.task_runner();
 
   bool called = false;
   base::RunLoop run_loop;
   worker_task_runner->PostTask(
-      FROM_HERE,
-      RelayCallbackToTaskRunner(
-          ui_task_runner.get(),
-          FROM_HERE,
-          base::Bind(&VerifyCalledOnTaskRunner, ui_task_runner, &called)));
+      FROM_HERE, RelayCallbackToTaskRunner(
+                     ui_task_runner.get(), FROM_HERE,
+                     base::Bind(&VerifyCalledOnTaskRunner,
+                                base::RetainedRef(ui_task_runner), &called)));
   worker_task_runner->PostTask(
       FROM_HERE,
       RelayCallbackToTaskRunner(
           ui_task_runner.get(), FROM_HERE, run_loop.QuitClosure()));
   run_loop.Run();
   EXPECT_TRUE(called);
 
   thread.Stop();
   base::RunLoop().RunUntilIdle();
 }
 
 TEST(DriveBackendCallbackHelperTest, PassNullFunctionTest) {
   base::MessageLoop message_loop;
   base::Closure closure = RelayCallbackToCurrentThread(
       FROM_HERE,
       base::Closure());
   EXPECT_TRUE(closure.is_null());
 }
 
 }  // namespace drive_backend
 }  // namespace sync_file_system